[llvm] [NVPTX][NFC] Refactor and cleanup NVPTXISelLowering call lowering 2/n (PR #137666)

[Artem Belevich via llvm-commits]

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@@ -444,52 +436,39 @@ enum ParamVectorizationFlags {
 // of the same size as ValueVTs indicating how each piece should be
 // loaded/stored (i.e. as a scalar, or as part of a vector
 // load/store).
-static SmallVector<ParamVectorizationFlags, 16>
+static SmallVector<unsigned, 16>
 VectorizePTXValueVTs(const SmallVectorImpl<EVT> &ValueVTs,
                      const SmallVectorImpl<uint64_t> &Offsets,
                      Align ParamAlignment, bool IsVAArg = false) {
   // Set vector size to match ValueVTs and mark all elements as
   // scalars by default.
-  SmallVector<ParamVectorizationFlags, 16> VectorInfo;
-  VectorInfo.assign(ValueVTs.size(), PVF_SCALAR);
+  SmallVector<unsigned, 16> VectorInfo;
 
-  if (IsVAArg)
+  if (IsVAArg) {
+    VectorInfo.assign(ValueVTs.size(), 1);
     return VectorInfo;
+  }
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Artem-B wrote:

We could just return an explicitly contructed temporary array here, and move the `VectorInfo` down to where we actually do something interesting with it.

https://github.com/llvm/llvm-project/pull/137666